Geometric permutations of disjoint unit spheres
نویسندگان
چکیده
منابع مشابه
Geometric permutations of disjoint unit spheres
We show that a set of n disjoint unit spheres in R admits at most two distinct geometric permutations if n ≥ 9, and at most three if 3 ≤ n ≤ 8. This result improves a Helly-type theorem on line transversals for disjoint unit spheres in R: if any subset of size 18 of a family of such spheres admits a line transversal, then there is a line transversal for the entire family.
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ژورنال
عنوان ژورنال: Computational Geometry
سال: 2005
ISSN: 0925-7721
DOI: 10.1016/j.comgeo.2004.08.003